Fair value measurements - Impact of changes in its own creditworthiness on certain financial liabilities (Detail) - JPY (¥) ¥ in Billions |
12 Months Ended | |
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Mar. 31, 2026 |
Mar. 31, 2025 |
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| Fair Value Disclosures [Abstract] | ||
| Changes recognized as a credit (debit) to other comprehensive income | ¥ (55) | ¥ 26 |
| Credit (debit) amounts reclassified to earnings | (1) | 0 |
| Cumulative credit balance recognized in accumulated other comprehensive income | ¥ 22 | ¥ 78 |
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- Definition Amount before tax, after reclassification adjustments, of appreciation (loss) in value of Own credit, Billion No definition available.
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- Definition Amount of unrealized gain (loss) related to Own credit adjustment, which was recorded in accumulated other comprehensive income. No definition available.
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- References No definition available.
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- Definition Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for unrealized gain (loss) from increase (decrease) in instrument-specific credit risk, realized upon derecognition of financial liability measured under fair value option. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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